Browser based free games
Play free and free-to-play games designed to be played direclty in a browser (this includes both browser-based games and flash games)
Here are some of the best browser games you can play directly online: MMORPGs, collectible card games, strategy games and more. Browser games usually doesn't require nothing more than an updated browser (Chrome, Firefox, Edge, Opera, etc.) and are playable on any PC or Mac. Some of them may require a Flash plugin.
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Mars Tomorrow
strategy / MMORTS
Game Fabrik

Mega victory! Sexy rock, paper, scissors
puzzle
Cleesh Haze

Might & Magic Heroes Online
RPG / MMORPG
Related Designs

Monochrome Mahjongg
puzzle / mahjong
Zygomatic

Monster Slayers
action / brawler
Nerdook

Pixel Town
strategy / city building
automatonvx

Popmundo
simulation
ExtraLives AB

Progress Quest
RPG / idle clicker
Eric Fredricksen

Questionaut
adventure / point & click
Amanita Design

Quick Fire Pool Instant
action
Miniclip

Rail Nation
simulation / management
Travian Games

Realm of the Mad God Exalt
RPG / MMORPG
Wild Shadow Studios

RPG MO
RPG / MMORPG
Marxnet

Sextris
puzzle / tile-matching
Sextris

Soccer Strip Quest
puzzle / tile-matching
Bad Suzy

Star Wars Combine
RPG / MMORPG
SWC Programming Team

Strip a Girlfriend!
puzzle
Empty Set

Strip Blackjack 3310
card game / strip poker
GGBot

Strip poker online
card game / strip poker
net-assembly

Strip the Difference
puzzle
Gang of Gamers

Supremacy 1914
strategy / wargame
Bytro Labs